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František Jiříček Pavel Tříska Jaroslav Vojta Ya. I. Likhter V. V. Korobovkin Reviewer V. Bumba 《Studia Geophysica et Geodaetica》1973,17(1):49-58
Summary The Interkosmos5 VLF experiment consisted of a spectrum analyser with twelve narrow-band channels and broadband measurements between0.07 and20 kHz using an analogue telemetry with a tape recorder on board. The apparatus used in the experiment is shortly described, some examples ofVLF phenomena observed are given and a review of all analogue data recorded is shown in a graphical calendar. 相似文献
125.
Václav Bucha Josef Horáček Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1973,17(4):321-336
Summary The paper brings a brief geological asessment of the sedimentational cycles, analyses the methods of collection and investigation of samples and the representativeness of the results obtained. Problems of magnetic cleaning and the types of demagnetization curves investigated are discussed. The continuous nature of the variations of the magnetic declination, inclination and remanent magnetization, determined by palaeomagnetic investigation of Quaternary sediments, is also discussed. The conclusion contains the principal facts about the dynamics of the geomagnetic field in the Quaternary and points out the possibility of applying them to the theory of the geomagnetic field, as well as to geological correlations. 相似文献
126.
The distribution of controlling pressure formations, occurring in the Northern Hemisphere during the winters (January and February) of the years 1952 – 1996, has been analysed. It was found that the deepening of the Icelandic and Aleutian pressure lows is connected not only with a particular QBO phase and level of geomagnetic activity (Bochníek et al., 1999) but also with a particular level of solar activity. 相似文献
127.
Approximate spectral analysis by least-squares fit 总被引:4,自引:0,他引:4
Petr Vaníček 《Astrophysics and Space Science》1969,4(4):387-391
An approximate method of spectral analysis called successive spectral analysis based upon the mean-quadratic approximation of an empirical function by generalised trigonometric polynomial with both unknown frequencies and coefficients is developed. A few quotations describing some properties of the method as well as one of the possible methods for numerical solution are given. 相似文献
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Huth Radan Mládek Richard Metelka Ladislav Sedlák Pavel Huthová Zuzana Kliegrová Stanislava Kyselý Jan Pokorná Lucie Halenka Tomáš Janoušek Martin 《Studia Geophysica et Geodaetica》2003,47(4):863-873
This note summarizes results of the first integration of regional numerical weather prediction model ALADIN in a climate mode. The ALADIN model, developed in an international cooperation led by Météo France, is operationally used for weather prediction. The grid step of the model is 12 km; the integration domain covers a major part of Europe. A one-month-long run has been performed with this model on observed boundary conditions (represented by assimilations by the global model ARPEGE). It is demonstrated that no excessive error is generated and accumulated in the model during the integration; hence the model is integrable for extended time periods and may serve a basis for a development towards a regional climate model. 相似文献
130.
Jan?Pa?avaEmail author Ivan?Vav?ín Ji?í?Fryda Vojtěch?Janou?ek Emil?Jelínek 《Mineralium Deposita》2003,38(3):298-311
The Ransko gabbro-peridotite massif in Eastern Bohemia is a strongly differentiated intrusive complex of Lower Cambrian age. The complex hosts low grade Ni-Cu ores mainly developed close to the contact of olivine-rich rocks with gabbros, in troctolites and, to a much lesser extent, in both pyroxene and olivine gabbros and plagioclase-rich peridotites. The ore zone is characterized by strong serpentinization and uralitization. The total Ni + Cu locally reaches up to 4 wt%. Anomalous concentrations of platinum-group elements (PGE's) (maximum 532 ppb Pd, 182 ppb Pt, 53 ppb Rh, 15 ppb Ru, 41 ppb Ir) were detected in samples of Cu-Ni and Ni-Cu ores (maximum 2.63 wt% Ni and 2.31 wt% Cu) from the Jezírka orebody. The main ore paragenesis includes pyrrhotite, pentlandite, chalcopyrite, cubanite, pyrite, magnetite, mackinawite, valleriite, ilmenite and sphalerite. During this work, michenerite, froodite, sperrylite, gold, native bismuth, altaite, tsumoite, hessite, an unnamed Bi-Ni telluride, cobaltite-gersdorffite and galena were newly identified. The host rocks originated through partial melting of a slightly depleted mantle source with noble metals scavenged from this primitive magma prior to the development of these rocks. 相似文献